The present invention relates to a line connector for pipelines and/or hose lines, in particular fuel lines, comprising a connecting body together with at least one line-connecting element.
Nowadays, known line connectors of the type mentioned consist predominantly of plastic. The line-connecting element is generally designed as a pointed profile (drive-in point) for the force- and/or form-fitting pushing-on of a line. In this arrangement, the connecting body can be designed as a coupling housing of a plug-in or socket part of a plug-in coupling. Line connectors of this type are used, for example, in motor vehicles in the region of the fuel lines. In this case, accident-induced (crash-induced) deformations of the vehicle are problematical, since the line connector may collide with engine and/or bodywork parts. In severe cases, this may result in the connector breaking, and the resultant unsealed state leads to a leakage of fuel which, when in contact with hot engine parts, could be ignited and therefore cause a vehicle fire.
FR-A-2 257 841 describes, for connecting two pipes, a plastic collar which is pressed onto the particular pipe on both sides using a respective union screw nut. This collar acts merely as a type of expansion joint.
FR-A-1 519 744 also describes a very similar arrangement, two pipes being connected via a rubber collar.
U.S. Pat. No. 4,810,008 describes a connector (fitting) for pipes in sprinkler systems, the said connector being intended to make simple exchange of leaking parts, for example pipe sections, possible. For this purpose, the connector has pipe connections which, via expansion-bellows-like intermediate sections, can be moved longitudinally in such a manner that they can be pushed axially onto the line and bonded in place.
GB-A-2 120 341 discloses a deformable pipe connector having an expansion- or concertinaed-bellows-like section which is formed by a metallic corrugated pipe and can be bent plastically about any desired angle.
The present invention is based on the object of improving a line connector of the type described at the beginning in such a manner that there is a noticeable reduction in the risk of damage, in particular of breakage, due to an externally applied force, especially a crash-induced force. At the same time, it should nevertheless be possible to produce the connector simply and cost-effectively.
According to the invention this is achieved in that the (or each) line-connecting element is connected to the connecting body via a transitional section which can be deformed elastically and/or plastically in such a manner that it can be bent or buckled transversely to a push-on axis of the line and relative to the connecting body while keeping the media sealed in, the line-connecting element together with the transitional section and the connecting body being formed from a single-piece moulding produced monolithically in a plastic moulding procedure in a multicomponent injection-moulding process from at least two different materials.
This advantageous refinement means that a risk of breakage in the region of the line connector is noticeably reduced because the properties of the connecting section mean that the media is kept sealed in even when the section buckles by up to at least 90xc2x0.
Although such severe buckling results in a plastic deformation impairing the flow cross section, with the result that the connector would have to be replaced, leakages are effectively avoided even in the case of such severe deformations. More minor deformations are possible even in the elastic range enabling the connector to continue to remain useable. In order to obtain the deformability which, according to the invention, is break-proof, the connecting section is configured, in particular empirically, with regard to its material-specific and/or shaping-induced properties, in such a manner that a predetermined deformation without leakage is possible. For this purpose, it has turned out to be particularly advantageous to use a thermoplastic without fibre reinforcement, in particular PA 12, for the connecting section, while the remaining sections consist of a thermoplastic, in particular the same thermoplastic, but with fibre reinforcement, in particular with a portion of glass fibre, preferably of PA 12-23% glass fibre. In addition, these materials are preferably electrically conductive receptors in order, in view of the preferred use in the fuel sphere, to avoid static charging and the formation of sparks possibly resulting therefrom. The design as a single-piece moulding which is injection-moulded monolithically advantageously means that the production is nevertheless simple and cost-effective.